Contrast enhancement is used to improve the picture quality of digital video and is often implemented using video processors. Although many image processing techniques exist for contrast enhancement, they are often unsuitable for an ASIC implementation because of their computational complexity and/or storage requirements. Additionally, many image processing techniques might not work for video, because the picture is continuously changing and many algorithms may be prone to artifacts like contouring and saturation of gray levels.
Because contrast enhancement is usually performed in a color space that separates brightness information from color, most algorithms operate on data in formats such as YCbCr, HSV, and the like. For video applications, the YCbCr format is typically used because it is the industry standard for video transmission and storage. The YCbCr format is also typically easier to convert to and from RGB than from HSV. The ease in conversion is important because the final display is usually configured to accept data in RGB format.
An appreciation of the present invention and its improvements can be obtained by reference to the accompanying drawings, which are briefly summarized below, to the following detailed description of illustrated embodiments of the invention, and to the appended claims.